fix: align ExternalModel BBR auth, body rewrite, and header match with /v1/models identity (opendatahub-io#401)

* fix: align ExternalModel BBR auth, body rewrite, and header match with /v1/models identity

* remove debug loggers

* Triggering CI build

Author: ishitasequeira

pkg/controller/externalmodel/reconciler.go

@@ -139,7 +139,6 @@ func (r *Reconciler) reconcileHTTPRoute(ctx context.Context, logger logr.Logger,
 		provider.Spec.Endpoint,
 		provider.Name,
 		model.Name,
-		ref.TargetModel,
 		model.Namespace,
 		ctrlcommon.DefaultTLSPort,
 		r.gatewayName(),
@@ -243,7 +242,7 @@ func commonLabels(modelName string) map[string]string {
 	}
 }
 
-func buildHTTPRoute(providerEndpoint, providerName, modelName, targetModel, namespace string, port int32, gatewayName, gatewayNamespace, routeTimeout string, labels map[string]string) *gatewayapiv1.HTTPRoute {
+func buildHTTPRoute(providerEndpoint, providerName, modelName, namespace string, port int32, gatewayName, gatewayNamespace, routeTimeout string, labels map[string]string) *gatewayapiv1.HTTPRoute {
 	gwNamespace := gatewayapiv1.Namespace(gatewayNamespace)
 	pathType := gatewayapiv1.PathMatchPathPrefix
 	pathPrefix := "/" + namespace + "/" + modelName
@@ -313,7 +312,7 @@ func buildHTTPRoute(providerEndpoint, providerName, modelName, targetModel, name
 								{
 									Name:  "X-Gateway-Model-Name",
 									Type:  &headerType,
-									Value: targetModel,
+									Value: modelName,
 								},
 							},
 						},

pkg/controller/externalmodel/reconciler_test.go

@@ -190,7 +190,7 @@ func TestReconcile_CreatesHTTPRoute(t *testing.T) {
 	// Two rules: path + header
 	require.Len(t, hr.Spec.Rules, 2)
 	assert.Equal(t, "/"+ns+"/gpt4", *hr.Spec.Rules[0].Matches[0].Path.Value)
-	assert.Equal(t, "gpt-4o", hr.Spec.Rules[1].Matches[0].Headers[0].Value)
+	assert.Equal(t, "gpt4", hr.Spec.Rules[1].Matches[0].Headers[0].Value)
 
 	// Backend ref points to provider's Service
 	assert.Equal(t, "my-openai", string(hr.Spec.Rules[0].BackendRefs[0].Name))
@@ -336,9 +336,9 @@ func TestReconcile_TwoModelsOneProvider(t *testing.T) {
 	assert.Equal(t, "shared-provider", string(hr1.Spec.Rules[0].BackendRefs[0].Name))
 	assert.Equal(t, "shared-provider", string(hr2.Spec.Rules[0].BackendRefs[0].Name))
 
-	// But different target models in header match
-	assert.Equal(t, "gpt-4o", hr1.Spec.Rules[1].Matches[0].Headers[0].Value)
-	assert.Equal(t, "gpt-3.5-turbo", hr2.Spec.Rules[1].Matches[0].Headers[0].Value)
+	// Header match uses modelName (ExternalModel CR name)
+	assert.Equal(t, "gpt4", hr1.Spec.Rules[1].Matches[0].Headers[0].Value)
+	assert.Equal(t, "gpt35", hr2.Spec.Rules[1].Matches[0].Headers[0].Value)
 
 	// Different path prefixes
 	assert.Equal(t, "/"+ns+"/gpt4", *hr1.Spec.Rules[0].Matches[0].Path.Value)
@@ -363,7 +363,7 @@ func TestCommonLabels(t *testing.T) {
 func TestBuildHTTPRoute(t *testing.T) {
 	hr := buildHTTPRoute(
 		"api.openai.com", "my-openai",
-		"gpt4", "gpt-4o",
+		"gpt4",
 		"models", 443,
 		"default-gateway", "openshift-ingress", "300s",
 		commonLabels("gpt4"),
@@ -385,10 +385,10 @@ func TestBuildHTTPRoute(t *testing.T) {
 	rule1 := hr.Spec.Rules[0]
 	assert.Equal(t, "/models/gpt4", *rule1.Matches[0].Path.Value)
 
-	// Rule 2: header-based match uses targetModel
+	// Rule 2: header-based match uses modelName (what /v1/models returns)
 	rule2 := hr.Spec.Rules[1]
 	assert.Equal(t, "X-Gateway-Model-Name", string(rule2.Matches[0].Headers[0].Name))
-	assert.Equal(t, "gpt-4o", rule2.Matches[0].Headers[0].Value)
+	assert.Equal(t, "gpt4", rule2.Matches[0].Headers[0].Value)
 
 	// Backend ref points to the PROVIDER's Service, not the model
 	for i, rule := range hr.Spec.Rules {
@@ -409,7 +409,7 @@ func TestBuildHTTPRoute(t *testing.T) {
 func TestBuildHTTPRoute_TargetModelDiffersFromName(t *testing.T) {
 	hr := buildHTTPRoute(
 		"bedrock.us-east-1.amazonaws.com", "my-bedrock",
-		"claude", "anthropic.claude-3-opus",
+		"claude",
 		"models", 443,
 		"my-gateway", "gateway-ns", "300s",
 		commonLabels("claude"),
@@ -419,8 +419,8 @@ func TestBuildHTTPRoute_TargetModelDiffersFromName(t *testing.T) {
 	assert.Equal(t, "claude", hr.Name)
 	assert.Equal(t, "/models/claude", *hr.Spec.Rules[0].Matches[0].Path.Value)
 
-	// Header match uses targetModel (provider-side name)
-	assert.Equal(t, "anthropic.claude-3-opus", hr.Spec.Rules[1].Matches[0].Headers[0].Value)
+	// Header match uses modelName (what /v1/models returns to clients)
+	assert.Equal(t, "claude", hr.Spec.Rules[1].Matches[0].Headers[0].Value)
 
 	// Backend points to provider Service
 	assert.Equal(t, "my-bedrock", string(hr.Spec.Rules[0].BackendRefs[0].Name))

pkg/plugins/model-provider-resolver/external_provider_reconciler.go

@@ -64,10 +64,11 @@ func (r *externalProviderReconciler) Reconcile(ctx context.Context, req ctrl.Req
 	}
 
 	config := buildConfigWithDefaults(provider.Spec.Provider, provider.Spec.Config)
+	authType := mapCRDAuthType(provider.Spec.Auth.Type)
 	r.store.addOrUpdateProvider(req.NamespacedName, &providerInfo{
 		provider:        provider.Spec.Provider,
 		endpoint:        provider.Spec.Endpoint,
-		auth:            auth.Auth(provider.Spec.Auth.Type),
+		auth:            authType,
 		secretName:      provider.Spec.Auth.SecretRef.Name,
 		secretNamespace: req.Namespace,
 		config:          config,
@@ -77,6 +78,16 @@ func (r *externalProviderReconciler) Reconcile(ctx context.Context, req ctrl.Req
 	return ctrl.Result{}, nil
 }
 
+// mapCRDAuthType maps CRD auth.type values to internal auth constants.
+// The ExternalProvider CRD uses "simple" for API-key auth, while the
+// internal auth package uses "apikey".
+func mapCRDAuthType(crdType string) auth.Auth {
+	if crdType == "simple" {
+		return auth.APIKey
+	}
+	return auth.Auth(crdType)
+}
+
 // buildConfigWithDefaults returns a config map that starts from provider-specific
 // defaults and then applies any user-supplied values from the CR on top.
 func buildConfigWithDefaults(providerName string, userConfig map[string]string) map[string]string {

pkg/plugins/model-provider-resolver/plugin.go

@@ -171,6 +171,10 @@ func (p *ModelProviderResolverPlugin) ProcessRequest(ctx context.Context, cycleS
 
 	ref := selectByWeight(modelInfo.refs)
 
+	if model != ref.targetModel {
+		request.SetBodyField("model", ref.targetModel)
+	}
+
 	cycleState.Write(state.ProviderKey, ref.provider)
 	cycleState.Write(state.ModelKey, ref.targetModel)
 	cycleState.Write(state.APIFormatKey, ref.apiFormat)